Fabian Winkler's PI (personal interpreters) is a set of small robotic devices, which deconstruct TV broadcasts' audio signals. The robots interpret the regular audio signal as control code and translate it into abstract rhythmic sounds.

PIs can be plugged into the sound output of a TV set (via RCA cables). Using suction cups, individual modules can be attached anywhere to the surface of the TV. These modules translate the sound output from TV broadcasts into movements of mechanized parts that scratch, hit and thump on the surface of the TV set using it as a resonant body. The audience still sees the images but hears only the deconstructed sounds created by the robotic modules - vaguely reminding them of the original soundtrack but challenging them to interpret it in new ways.

For an intervention on images, and in a sousveillance/surveillance context this time, Austrian activists Quintessenz created an anonymous surveillance system that uses a face-recognition software to place a black stripe over the eyes of people whose images are recorded (via Wired).

New Scientist reported today on a video surveillance system that scrambles people's faces to protect them from unwarranted monitoring. Developed by Swiss company EMITALL Surveillance, the algorithm of the technology singles out any people in a video feed, on the basis of their movement, and disguises them digitally while leaving the rest of the scene intact (Videos 1, 2 and 3). Only those in possession of the encryption key can unlock the scrambled regions and identify the people shown on-screen.

The system can even use different encryption keys to scramble the identity of particular people under surveillance, says Touradj Ebrahimi, founder of EMITALL Surveillance (thanks Emily!)

More broadcast disruption: SVEN - Surveillance Video Entertainment Network, a real-time video performance system that detects when people look like rock stars instead of criminals. Once a potential rock star is detected, music video effects are triggered so the surveillance stars get a treatment worthy of Cecil B himself; TV Predator, a picture frame that attacks the tv and prevent it from working properly; OiTV, a misbehaving attention-seeking TV.

Plans to spring-clean space junk orbiting Earth could result in the loss of irreplaceable historical artefacts, warns Alice Gorman of Flinders University in Adelaide. The researcher, who has previously called for space junk to be World Heritage listed, says it's time to assess the value of some of the millions of objects currently orbiting Earth.

Space junk ranges from tiny scraps just millimetres in size to whole satellites. While some space junk undergoes an "automatic clean-up regime" by burning up when it re-enters the atmosphere, other items need to be physically removed.

Current proposals include using ground-based lasers to put objects off orbit and speed the rate of their burn-up, sending out 'space tugs' as roving garbage collectors or using tethers to rope and haul in bits of space debris.

Among the items that should recognised for their heritage value are the Vanguard One satellite, launched in 1958 and the oldest human object in space, and FedSat, the Australian designed and built satellite.

Preserving items like these could provide evidence of a nation's presence in space or help reconstruct a history of space exploration, says Gorman.

After a four-year inquiry, they have concluded that most sightings can be explained by a little-understood atmospheric phenomenon.

Glowing "plasmas" of gas are created by charges of electricity. Air flows then sculpt the plasmas into round or cigar-shaped objects which appear to fly at extraordinary speeds through the sky.

Such plasmas can play tricks on the mind, creating vivid impressions. In addition, because plasmas are electrically charged, they can change shape or colour if hit by another energy source, such as a radio signal sent by a UFO spotter. "This has led ‘ufologists’ to imagine that an ‘alien response’ is being given to their signals," the report adds. As a result, UFO witnesses may not be mad but instead suffering from "extended memory retention and repeat experiences" induced by the plasmas.

The report goes on to recommend that the findings on UFOs could be developed for "novel military applications", adding that Russia is already investigating such weapons.

Tomas Saraceno will be at theThe Curve 11 May 2006 - 16 July 2006, Barbican Art Gallery, London. His long-term project draws on Physics, Chemistry, Engineering, and artistic disciplines in order to create a floating Utopia that would drift among the clouds to solve the world's exploding population problem.

A few decades ago, some architects had a similar vision of suspended or moving communities: Superstudio's City of the Hemispheres and Archigram's moving units, Seaside Bubbles and Yona Friedman's spatial cities. Friedman developed his principles shortly after the Second World War, a period in which acute housing shortage and urban rebuilding had to be addressed. The architect proposed huge structures, supported on columns, in which residents could build their own dwellings. He later developed manuals in the form of comic-books that enabled people to take decisions about the design of their own living environment (audio interview of the architect in french.)

Commercial space travel is becoming a reality, says Lin, and the public needs confidence that governments, scientists and astronauts are considering the consequences of exploring space.

For instance, we need a fair process for commercialising or claiming property in space to avoid the kind of "chaotic land-grab" that occurred with internet domain names. There are legal disputes already. Despite UN treaties declaring space as commonly-owned, he says lawsuits have been filed to lay claim to asteroids.

Lin says it is important to have a justifiable reason for exploring space. "Are reasons such as for adventure, wanderlust or 'backing up the biosphere' good enough to justify our exploration of space?"

Lin says issues such as polluting space, the proliferation of military technologies in space and the safety of space travellers should also be considered. "Have we learned enough about ourselves and our history to avoid the same mistakes as we have made on Earth?"

Finally, some critics suggest it may be better to spend money on alleviating poverty and hunger, providing access to clean and affordable water and energy, and addressing other issues including human rights violations.

In order to help alien visitors to land their UFO's safely in the Netherlands, Martin Riebeek in collaboration with the Dutch city of Houten (near Utrecht) have imagined to create an UFO landing pad on the roundabouts at the exit of the A27 highway.

On the eastern roundabout, a UFO platform will be built with light green reflecting, artificial coating. In the middle, a big red "U" (for UFO) has the role to greet alien cultures politely.

On the western roundabout, the light of the six meter high traffic tower will change its colour as soon as traffic on the highway has low intensity. Then the UFOs will know that they can start their landing. The intermediate 300 meters will be lit with blue lights on both sides of the road, much like the ones at airports.